I have a SF1 Jet P90 that I like but it was like (3) P90s are too many! A Gretsch Filtertron will fit the Franz routing. So I bought a GFTron Modern Lead for the bridge and then a bridge & neck set of GF Hard Trons for the center and neck positions - all in black.. I had to make up three 3/16 " spacer blocks screwed to the center bock in order to get a good PU height setting. What a nice result, The mixture of pickups gives me 5 actual different sounds with the 5 position selector sw. The P 90s really didn't because there was 1 bridge and 2 neck PUs in the three positions. The Modern Lead and Heavey set are all Alnico V magnets but they are wound 8.0K, 7.1K ans 6.0K in that order. I really like the Gretchy sparkle and the Lead heads toward a humbucker with jangle. Lovin' y new Jet "tron"!